Freezing tunnel



Patented June 13, 1950 FREEZING TUNNEL Franciscus A. A. M. Allard, Bloemendaal, Netherlands, assignor to N. V. Ijsfabriek en Koelhuis Ijsvries, Ijmuiden, Netherlands Application December 29, 1947, Serial No. 794,306

. In the Netherlands May 6, 1944 Section 1, Public Law 690, August 8, 1946 Patent expires May 6, 1964 1 Claim.

The invention relates to a freezing tunnel comprising one or a plurality of series of tubes or one or a plurality of similar conduits for a refrigerant, arranged next to and parallel to one another in the longitudinal direction of the tunnel.

For conveying the goods to be frozen through such a tunnel use has hitherto been made of conveying devices by means of which the goods are passed through the tunnel. For this purpose a belt conveyor is usually employed on which the goods or the package containing said goods are placed in order to be moved through the tunnel.

The use of a belt conveyor, however, means an unnecessary complication which may lead to breakdowns.

The object of the invention is to avoid such breakdowns and, moreover, to effect a better and more efficient cooling of the goods.

According to the invention the cooling-pipes or the other conduits for the refrigerant are to this end adapted to support and to guide the goods to be treated or the containers intended to receive these goods during their travel on the said pipes or conduits from the feed-end to the discharge-end of the tunnel.

The movement of the goods to be treated along the cooling-pipes or the other conduits for the refrigerant may be effected in a particularly suitable manner according to the invention by so arranging them that they slant down from the feed-end to the discharge-end of the tunnel in such a manner that the goods or the containers are-by their own weightcaused to slide down over them.

According to the invention, however, use may also be made of a device especially intended for conveying the goods to be cooled.

Since this device need not perform a carrying function it may consist of cables or ropes provided with protruding pins or other means for advancing the goods, which device is much simpler than a carrying conveyor, while the risk of the device freezing up is less great.

In illustration of the invention an embodiment of the freezing tunnel will be described with reference to the drawing.

Fig. 1 shows a vertical longitudinal section of the freezing tunnel, while Fig. 2 shows a section taken on the line IIII in Fig. 1.

According to the diagrammatic drawing the freezing tunnel consists of a tubular body 'I placed slant-wise, the walls of which are made of or stuffed with a highly thermal-insulating material.

In the freezing tunnel some series of tubes 2 are so arranged as to be spaced from and located above one another, each series consisting of a number of tubes running next to and parallel to one another in the longitudinal direction of the tunnel.

The refrigerant which is to effect the chilling gfbthe goods to be treated flows through the said u es.

The freezing tunnel is provided with an airlock 3 at its feed-end and with an air-lock 4 at its discharge-end.

Supporting members 5 and 6 linked up with the cooling tubes, extend through these air-locks, by way of which members the goods or containers are fed into or removed from the freezing tunnel.

According to the embodiment the goods to be frozen are placed in metal containers 1 which are then slid over the supporting members 5 and via the air-lock 3 into the freezing tunnel, where they rest on the cooling tubes of one of the series 2.

Owing to these tubes sloping down the containers 1 will slide along the tubes and finally come to rest on the supporting members 6, to be removed from the freezing tunnel by way of the air-lock 4 and the supporting members 6.

During the containers 1 sliding along the cooling tubes they are in intimate contact therewith and as a result they are effectively refrigerated together with the goods which they contain. An aditional circumstance greatly promoting the refrigeration results from the scraping action of these containers on the tubes keeping the side of the cooling-tubes along which the containers I slide, free from the water vapour freezing up on said tubes in the form of boar-frost. This is instrumental in establishing the direct contact between the cooling-tubes and the containers moving along them.

A further advantage of the construction of the freezing tunnel according to the invention consists in that the conveyance of the goods or of the containers through the tunnel can be effected-without separate conveying devices by the weight of the goods themselves.

Moreover it may be of advantage from an operational point of view for the goods to be delivered on another storey than the one where they were fed into the tunnel.

Nevertheless it is very well possible also to apply the principle according to the invention to a freezing tunnel in which the cooling-tubes are arranged horizontally and even to a tunnel in which said tubes slope up. In these cases, however, a device must be provided by means of which the goods or the containers are dragged along the cooling-tubes.

For this purpose use may be made, for example, of endless ropes arranged parallel to the cooling tubes and provided with means which catch behind the goods or the containers and thereby slide them over the cooling tubes.

I claim:

A freezing tunnel comprising a horizontal platform both at the feed-end of the tunnel and at 10 the discharge-end thereof, said discharge end being located at a lower level than said feed-end, a series of mutually parallel longitudinal cooling tubes being arranged between those edges of said platforms which face each other so as to allow 15 the goods to be frozen to slide down under gravity over the inclined tubes from the feed-platform to the discharge-platform.

FRANCISCUS A. A. M. ALLARD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,004,358 Bronson Sept. 26, 1911 2,019,551 Varney Nov. 5, 1935 2,237,255 Finnegan Apr. 1, 1941 

